KiCad "Thermal relief connection to zone incomplete" (starved thermal)
KiCad design rule check (PCB) message: Thermal relief connection to zone incomplete (starved_thermal in kicad-cli reports).
What it means
A pad connected to a pour with thermal reliefs needs a minimum number of spokes reaching the zone (two by default). KiCad reports this warning when fewer spokes actually make it, usually because a nearby track, via or the board edge blocks the others. The pad may still be connected, but through a thin path that can heat up or fail.
Common causes
- Vias, tracks or other pads sitting where the spokes would go.
- A thermal gap or spoke width that is too large for the space around the pad.
- The pad sitting near the edge of the pour, so some spokes have nowhere to land.
How to fix it
- Move the obstacle, or rotate the footprint so the spokes have room.
- Reduce the thermal relief gap or widen the spokes in the zone properties (or per pad in the footprint).
- Switch that pad to a solid connection if it does not need thermal relief for soldering.
- Lower the zone's minimum spoke count only if one spoke really carries enough current.
Where the setting lives
Zone Properties → thermal relief gap, spoke width and minimum spoke count; pad properties → zone connection.
Good to know
KiCad counts a track that leaves the pad and ends inside the fill as a spoke, so a short track into the pour can satisfy the check.
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Checked against KiCad 10's source and documentation. Last reviewed 2026-11-07.
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